Overview. Caffeine is a chemical primarily found in coffee and tea, but which also appears in various sodas, sports drinks and foods. It is a stimulant, therefore causing changes in metabolism as well as increases in focus and energy. Caffeine is addictive and can cause withdrawal following cessation after frequent use.
robot. 1  a machine that resembles a human and does mechanical, routine tasks on command. 2  a person who acts and responds in a mechanical, routine manner, usually subject to another's will; automaton. 3  any machine or mechanical device that operates automatically with humanlike skill.
Machinery. a part, as a disk, wheel, or section of a shaft, having cut teeth of such form, size, and spacing that they mesh with teeth in another part to transmit or receive force and motion. an assembly of such parts. one of several possible arrangements of such parts in a mechanism, as an automobile transmission, for affording different relations ...